Project #66341 - Distributions/statistics

Assume the speed of vehicles along a stretch of I-10 has an approximately
normal distribution with a mean of 71 and a standard deviation of 8mph.
a.テつ テつ テつ The current speed limit is 65 mph. What is the proportion of
vehicles less than or equal to the speed limit?
b.テつ テつ テつ What proportion of the vehicles would be going less than 50 mph?
c.テつ テつ テつ A new speed limit will be initiated such that approximately 10% of
vehicles will be over the speed limit. What is the new speed limit based on
this criterion?
d.テつ テつ テつ In what way do you think the actual distribution of speeds differs
from a normal distribution?
#2
A group of students at a school takes a history test. The distribution is
normal with a mean of 25, and a standard deviation of 4.
a.テつ テつ テつ Everyone who scores in the top 30% of the distribution gets a
certificate. What is the lowest score someone can get and still earn a
certificate?
b.テつ テつ テつ The top 5% of the scores get to compete in a statewide history
contest. What is the lowest score someone can get and still go onto compete
with the rest of the state?
#3
Use the normal distribution to approximate the binomial distribution and
find the probability of getting 15 to 18 heads out of 25 flips. Compare this
to what you get when you calculate the probability using the binomial
distribution. Write your answers out to four decimal places.
#4
The patient recovery time from a particular surgical procedure is normally
distributed with a mean of 5.3 days and a standard deviation of 2.1 days.
What is the median recovery time?
a.テつ テつ テつ 2.7
b.テつ テつ テつ 5.3
c.テつ テつ テつ 7.4
d.テつ テつ テつ 2.1
#5
Height and weight are two measurements used to track a child's development.
The World Health Org measures child development by comparing the weights of
children who the same height and gender. In 2009, weights for all 80 cm
girls in the reference population had a mean of 10.2 kg and standard
deviation of 0.8 kg. Weights are normally distributed. X~N(10.2,0.8)
Calculate z-scores that correspond to the following weights and interpret
them.
a.テつ テつ テつ 11 kg
b.テつ テつ テつ 7.9 kg
c.テつ テつ テつ 12.2 kg
#6
Suppose that the distance of fly balls hit to the outfield is normally
distributed with a mean of 250 ft and standard deviation of 50 ft.
a.テつ テつ テつ If X=distance in ft for a fly ball then X~___(___,____)
b.テつ テつ テつ If one fly ball is randomly chosen from this distribution, what is
the probability that this ball travelled fewer than 220 ft. Sketch the
graph. Scale the horizontal axis X. Shade the region corresponding to the
probability. Find the probability.
c.テつ テつ テつ Find the 80th percentile of the distribution of fly balls. Sketch
the graph, and write the probability statement.
#7
Facebook provides a variety of statistics on its Web site that detail the
growth and popularity of the site. On average, 28% of 18-34 year olds check
their Facebook profiles before getting out of bed in the morning. Suppose
this percentage follows a normal distribution with a standard deviation of
5%.
a.テつ テつ テつ Find the probability that the percent of 18-34 year olds who check
Facebook before getting out of bed in the morning is at least 30.
b.テつ テつ テつ Find the 95th percentile and express it in a sentence.
#8
Suppose that the distance of fly balls hit to the outfield (in baseball) is
normally distributed with a mean of 250 ft and a standard deviation of 50
ft. We randomly sample 49 fly balls.
a.テつ テつ テつ If X=average distance in feet for 49 fly balls, then
X~____(___,____)
b.テつ テつ テつ What is the probability that the 49 balls travelled an average of
less than 240 ft? Sketch the graph. Scale the horizontal axis for X. Shade
the region corresponding to the probability. Find the probability.
c.テつ テつ テつ Find the 80th percentile of the distribution of the average of 49
fly balls.
#9
Which of the following is NOT TRUE about the distribution for averages?
a.テつ テつ テつ Mean, median, and mode are equal
b.テつ テつ テつ Area under the curve is one
c.テつ テつ テつ Curve never touches the x-axis
d.テつ テつ テつ Curve is skewed to the right
#10
A typical adult has an average IQ score of 105 with a standard deviation of
0.065 g. If a vending machine is designed to accept coins whose weights
range from 5.111 g to 5.291 g, what is the expected number of rejected coins When 280 randomly selected coins are inserted into the machine?

Subject Mathematics
Due By (Pacific Time) 04/12/2015 08:00 pm
Report DMCA
TutorRating
pallavi

Chat Now!

out of 1971 reviews
More..
amosmm

Chat Now!

out of 766 reviews
More..
PhyzKyd

Chat Now!

out of 1164 reviews
More..
rajdeep77

Chat Now!

out of 721 reviews
More..
sctys

Chat Now!

out of 1600 reviews
More..
sharadgreen

Chat Now!

out of 770 reviews
More..
topnotcher

Chat Now!

out of 766 reviews
More..
XXXIAO

Chat Now!

out of 680 reviews
More..
All Rights Reserved. Copyright by AceMyHW.com - Copyright Policy